Specification Sheet
NGK Spark Plug Specication Chart
44
NGK Racing NGK Standard
Part
No.
Stock
No.
Image
Part
No.
Stock
No.
Image
Racing Spark Plugs
8mm Spark Plugs
3/4” Reach
13mm Hex R847-10 3176 215 AC
Surface Discharge R847-11 4653 215 AC
Gasket, Stud
Resistor
10mm Spark Plugs
1/2” Reach R0161-9 4156 156 DR
5/8” Hex R0161-10 4778 156 DR
Semi-Surface Discharge R0161-11 5187 156 DR
Gasket, Loose
Non-Resistor
3/4” Reach
5/8” Hex R0045J-9 5861 286 IC
Surface Discharge R0045J-10 7400 286 IC
Gasket, Solid R0045J-11 7043 286 IC
Non-Resistor
3/4” Reach
5/8” Hex R0045Q-10 4216 286 IC
Surface Discharge R0045Q-11 5957 286 IC
Gasket, Loose
Resistor
3/4” Reach R0373A-8 3407 168 EB
5/8” Hex
Fine Wire, Iridium R0373A-9 3388 168 EB
Gasket, Stud
Resistor R0373A-10 4940 168 EB
R0373A-11 5566 168 EB
3/4” Reach
5/8” Hex R0406A-8 1480 168 EB
Fine Wire, Iridium R0406A-9 1481 168 EB
Gasket, Solid
Resistor
3/4” Reach
5/8” Hex R0409B-8 7791 253 IC
Fine Wire R0409B-9 7792 253 IC
Gasket, Stud R0409B-10 5897 253 IC
Resistor, Partial Thread
26.5mm Reach
14mm Hex R0451B-8 9356 338 JR
Fine Wire, Iridium
Gasket, Solid
Resistor
12mm Spark Plugs
3/4” Reach
5/8” Hex R2349-9 4418 128 AC
Surface Discharge R2349-10 6839 128 AC
Gasket, Solid
Resistor R2349-11 4583 128 AC
3/4” Reach
5/8” Hex R2525-9 4735 128 IC
Platinum R2525-10 5281 128 IC
Gasket, Loose R2525-11 5998 128 IC
Resistor
26.5mm Reach
5/8” Hex R2556B-8 6453 329 JI
Iridium R2556B-9 4962 329 JI
Gasket, Solid R2556B-10 1997 329 JI
Resistor
NGK Racing NGK Standard
Part
No.
Stock
No.
Image
Part
No.
Stock
No.
Image
Racing Spark Plugs
14mm Spark Plugs
3/8” Reach R5670-5 2298 35 DC XR5 3332 214 DC
13/16” Hex R5670-6 2746 35 DC
Projected R5670-7 2891 35 DC
V-Power R5670-8 3354 35 DC
Gasket, Loose R5670-9 3913 35 DC
Non-Resistor
.460” Reach R5673-6 2405 118 HQ BR6FS 4323 129 CS
5/8” Hex R5673-7 2817 118 HQ
V-Power R5673-8 3249 118 HQ
Tapered, Loose R5673-9 3442 118 HQ
Non-Resistor R5673-10 4050 118 HQ
.460” Reach R5674-6 4449 255 HB UR6 7773 47 HB
5/8” Hex R5674-7 5034 255 HB
V-Power R5674-8 5657 255 HB
Projected R5674-9 6468 255 HB
Tapered, Loose R5674-10 6702 255 HB
Non-Resistor
1/2” Reach R5525-7 6241 24 T
13/16” Hex R5525-8 7383 24 T
Gasket, Solid R5525-9 3914 24 T
Non-Resistor R5525-10 2098 24 T
R5525-11 2844 24 T
1/2” Reach
13/16” Hex
Gold Palladium
Gasket, Loose R5530-11 7958 24 BG
Non-Resistor
.708” Reach R5724-8 7317 320 IZ
5/8” Hex R5724-9 7891 320 IZ
Projected R5724-10 7993 320 IZ
Tapered, Loose
Non-Resistor
3/4” Reach R5671A-7 4091 212 IV
5/8” Hex R5671A-8 4554 212 IV
V-Power R5671A-9 5238 212 IV
Gasket, Solid R5671A-10 5820 212 IV
Non-Resistor R5671A-11 6596 212 IV
3/4” Reach
5/8” Hex R5672A-8 7173 3 L BKR8EIX 2668 204 FO
V-Power, Projected R5672A-9 7405 3 L BKR9EIX 2669 204 FO
Gasket, Solid R5672A-10 7942 3 L
Non-Resistor
3/4” Reach R7282-7 4587 21 IC
5/8” Hex R7282-9 4753 21 IC
Iridium, Short R7282-10 2000 21 IC
Gasket, Solid R7282-105 4985 21 IC
Resistor R7282-11 2001 21 IC
3/4” Reach
5/8” Hex R5883-9 2780 212 AC
Surface Discharge R5883-11 6077 212 AC
Gasket, Solid
Non-Resistor
3/4” Reach
5/8” Hex R6711-9 3167 212 AC
Semi-Surface Discharge R6711-10 2919 212 AC
Gasket, Solid
Non-Resistor
3/4” Reach
5/8” Hex
Semi-Surface Discharge R6601-10 4017 212 AC
Gasket, Solid R6601-11 4586 212 AC
Resistor
Spark plug charts are sorted by thread size, thread reach, hex size. Hotter plugs are listed above the colder plugs. Plug images are
located on the opposite page.
Due to the extreme modications in racing applications, these spark plugs are not warranted